Anyone running a 904 behind a 340?
If you want to sweat details to give the illusion that I don’t know what I talking about, that’s your choice. You thought I didn’t know how a transbrake releases.
I think you are not looking at your own posted chart. It clearly shows that the rear band is on in manual low. It clearly shows the low band is off in second gear and that the front band is on in second gear. In order to get a clean 1-2 shift the low reverse band on a transbrake must release fully before the front band comes on. All transbrakes, all of them apply the low band when the brake is on. You have to or you would break the sprag. How and when that band is released varies by manufacturer. Thats all I am saying. Because of this variation, it is still possible to hurt the roller clutch if the slicks lose traction and then regain it again after you have left the line if the car is still in first gear because the low band may have already released.
A better stronger roller clutch might prevent
A failure in that scenario. To prevent this, manufacturers try to leave the low band on as long as possible, but leaving it on too long can mess up the 1-2 shift with band overlap.
Drive any bone stock torqueflite in manual low (when the band is on) and quickly throw the shifter to 2nd gear and tell me what kind of shift quality you get. The shift is crap because the band doesn’t release fast enough.
I build all my own trannys too. Look at the photos in my signature. John cope is not some guy and neither is Paul Forte of turbo action.
These guys are premiere torqueflite valve body designers. I learned something too when they explained it to me.
Trans act used to have 2-3 different transbrake versions.
Since all brakes apply the band when the brake is on, what do you think the low band apply option is in his other models ? It refers to when it shuts off and the billet models deal with that better with enlarged and rerouted oil circuits.
First of all, I know John Cope, I buy HP parts through John.
Second, your posts are jumbled and meander all over the place.
You seem to be confusing releasing the transbrake with the 1-2 shift, they are not related.
Transbrake on:
Rear band , Rear clutch,
Front clutch on.
(Trans is now in 1st and Reverse gear at the same time)
Transbrake Off and launching in 1st gear:
Rear band, Rear clutch on.
(Front clutch was dumped via Transbrake switch to release Reverse gear and unlock the trans)
Second gear:
Front band, Rear clutch on.
(Rear band dumped, front band applied)
What full manual VB designers have been trying to do is cut down the overlap time between releasing the Rear band ( dumping 1st gear) and applying the front band ( applying second gear). That's obviously easier to do with a billet VB.
And they seem to have done a good job of it.
The only manual VB's I use, have rear band apply in 1st. Doesn't matter if it has a transbrake of not.
From what I can see, all of Johns VB's ( either just Manual or with a Transbrake) have the rear band apply until the trans shift into second gear.
To be honest, I'm not really sure what your trying to get at?
